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Type I D-branes in an H-flux and twisted KO-theory

V. Mathai·M. K. Murray·D. Stevenson
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Abstract

Witten has argued that charges of Type I D-branes in the presence of an H-flux, take values in twisted KO-theory. We begin with the study of real bundle gerbes and their holonomy. We then introduce the notion of real bundle gerbe KO-theory which we establish is a geometric realization of twisted KO-theory. We examine the relation with twisted K-theory, the Chern character and provide some examples. We conclude with some open problems.

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V. Mathai, M. K. Murray, D. Stevenson. 2003-10-24. Type I D-branes in an H-flux and twisted KO-theory. https://doi.org/10.1088/1126-6708%2F2003%2F11%2F053

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